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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Generic driver for memory-mapped GPIO controllers.
4 *
5 * Copyright 2008 MontaVista Software, Inc.
6 * Copyright 2008,2010 Anton Vorontsov <cbouatmailru@gmail.com>
7 *
8 * ....``.```~~~~````.`.`.`.`.```````'',,,.........`````......`.......
9 * ...`` ```````..
10 * ..The simplest form of a GPIO controller that the driver supports is``
11 * `.just a single "data" register, where GPIO state can be read and/or `
12 * `,..written. ,,..``~~~~ .....``.`.`.~~.```.`.........``````.```````
13 * `````````
14 ___
15_/~~|___/~| . ```~~~~~~ ___/___\___ ,~.`.`.`.`````.~~...,,,,...
16__________|~$@~~~ %~ /o*o*o*o*o*o\ .. Implementing such a GPIO .
17o ` ~~~~\___/~~~~ ` controller in FPGA is ,.`
18 `....trivial..'~`.```.```
19 * ```````
20 * .```````~~~~`..`.``.``.
21 * . The driver supports `... ,..```.`~~~```````````````....````.``,,
22 * . big-endian notation, just`. .. A bit more sophisticated controllers ,
23 * . register the device with -be`. .with a pair of set/clear-bit registers ,
24 * `.. suffix. ```~~`````....`.` . affecting the data register and the .`
25 * ``.`.``...``` ```.. output pins are also supported.`
26 * ^^ `````.`````````.,``~``~``~~``````
27 * . ^^
28 * ,..`.`.`...````````````......`.`.`.`.`.`..`.`.`..
29 * .. The expectation is that in at least some cases . ,-~~~-,
30 * .this will be used with roll-your-own ASIC/FPGA .` \ /
31 * .logic in Verilog or VHDL. ~~~`````````..`````~~` \ /
32 * ..````````......``````````` \o_
33 * |
34 * ^^ / \
35 *
36 * ...`````~~`.....``.`..........``````.`.``.```........``.
37 * ` 8, 16, 32 and 64 bits registers are supported, and``.
38 * . the number of GPIOs is determined by the width of ~
39 * .. the registers. ,............```.`.`..`.`.~~~.`.`.`~
40 * `.......````.```
41 */
42
43#include <linux/bitops.h>
44#include <linux/compiler.h>
45#include <linux/err.h>
46#include <linux/init.h>
47#include <linux/io.h>
48#include <linux/ioport.h>
49#include <linux/log2.h>
50#include <linux/mod_devicetable.h>
51#include <linux/module.h>
52#include <linux/platform_device.h>
53#include <linux/property.h>
54#include <linux/slab.h>
55#include <linux/spinlock.h>
56#include <linux/types.h>
57
58#include <linux/gpio/driver.h>
59
60#include "gpiolib.h"
61
62static void bgpio_write8(void __iomem *reg, unsigned long data)
63{
64 writeb(data, reg);
65}
66
67static unsigned long bgpio_read8(void __iomem *reg)
68{
69 return readb(reg);
70}
71
72static void bgpio_write16(void __iomem *reg, unsigned long data)
73{
74 writew(data, reg);
75}
76
77static unsigned long bgpio_read16(void __iomem *reg)
78{
79 return readw(reg);
80}
81
82static void bgpio_write32(void __iomem *reg, unsigned long data)
83{
84 writel(data, reg);
85}
86
87static unsigned long bgpio_read32(void __iomem *reg)
88{
89 return readl(reg);
90}
91
92#if BITS_PER_LONG >= 64
93static void bgpio_write64(void __iomem *reg, unsigned long data)
94{
95 writeq(data, reg);
96}
97
98static unsigned long bgpio_read64(void __iomem *reg)
99{
100 return readq(reg);
101}
102#endif /* BITS_PER_LONG >= 64 */
103
104static void bgpio_write16be(void __iomem *reg, unsigned long data)
105{
106 iowrite16be(data, reg);
107}
108
109static unsigned long bgpio_read16be(void __iomem *reg)
110{
111 return ioread16be(reg);
112}
113
114static void bgpio_write32be(void __iomem *reg, unsigned long data)
115{
116 iowrite32be(data, reg);
117}
118
119static unsigned long bgpio_read32be(void __iomem *reg)
120{
121 return ioread32be(reg);
122}
123
124static unsigned long bgpio_line2mask(struct gpio_chip *gc, unsigned int line)
125{
126 if (gc->be_bits)
127 return BIT(gc->bgpio_bits - 1 - line);
128 return BIT(line);
129}
130
131static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio)
132{
133 unsigned long pinmask = bgpio_line2mask(gc, gpio);
134 bool dir = !!(gc->bgpio_dir & pinmask);
135
136 if (dir)
137 return !!(gc->read_reg(gc->reg_set) & pinmask);
138 else
139 return !!(gc->read_reg(gc->reg_dat) & pinmask);
140}
141
142/*
143 * This assumes that the bits in the GPIO register are in native endianness.
144 * We only assign the function pointer if we have that.
145 */
146static int bgpio_get_set_multiple(struct gpio_chip *gc, unsigned long *mask,
147 unsigned long *bits)
148{
149 unsigned long get_mask = 0;
150 unsigned long set_mask = 0;
151
152 /* Make sure we first clear any bits that are zero when we read the register */
153 *bits &= ~*mask;
154
155 set_mask = *mask & gc->bgpio_dir;
156 get_mask = *mask & ~gc->bgpio_dir;
157
158 if (set_mask)
159 *bits |= gc->read_reg(gc->reg_set) & set_mask;
160 if (get_mask)
161 *bits |= gc->read_reg(gc->reg_dat) & get_mask;
162
163 return 0;
164}
165
166static int bgpio_get(struct gpio_chip *gc, unsigned int gpio)
167{
168 return !!(gc->read_reg(gc->reg_dat) & bgpio_line2mask(gc, gpio));
169}
170
171/*
172 * This only works if the bits in the GPIO register are in native endianness.
173 */
174static int bgpio_get_multiple(struct gpio_chip *gc, unsigned long *mask,
175 unsigned long *bits)
176{
177 /* Make sure we first clear any bits that are zero when we read the register */
178 *bits &= ~*mask;
179 *bits |= gc->read_reg(gc->reg_dat) & *mask;
180 return 0;
181}
182
183/*
184 * With big endian mirrored bit order it becomes more tedious.
185 */
186static int bgpio_get_multiple_be(struct gpio_chip *gc, unsigned long *mask,
187 unsigned long *bits)
188{
189 unsigned long readmask = 0;
190 unsigned long val;
191 int bit;
192
193 /* Make sure we first clear any bits that are zero when we read the register */
194 *bits &= ~*mask;
195
196 /* Create a mirrored mask */
197 for_each_set_bit(bit, mask, gc->ngpio)
198 readmask |= bgpio_line2mask(gc, bit);
199
200 /* Read the register */
201 val = gc->read_reg(gc->reg_dat) & readmask;
202
203 /*
204 * Mirror the result into the "bits" result, this will give line 0
205 * in bit 0 ... line 31 in bit 31 for a 32bit register.
206 */
207 for_each_set_bit(bit, &val, gc->ngpio)
208 *bits |= bgpio_line2mask(gc, bit);
209
210 return 0;
211}
212
213static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val)
214{
215}
216
217static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
218{
219 unsigned long mask = bgpio_line2mask(gc, gpio);
220 unsigned long flags;
221
222 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
223
224 if (val)
225 gc->bgpio_data |= mask;
226 else
227 gc->bgpio_data &= ~mask;
228
229 gc->write_reg(gc->reg_dat, gc->bgpio_data);
230
231 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
232}
233
234static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio,
235 int val)
236{
237 unsigned long mask = bgpio_line2mask(gc, gpio);
238
239 if (val)
240 gc->write_reg(gc->reg_set, mask);
241 else
242 gc->write_reg(gc->reg_clr, mask);
243}
244
245static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val)
246{
247 unsigned long mask = bgpio_line2mask(gc, gpio);
248 unsigned long flags;
249
250 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
251
252 if (val)
253 gc->bgpio_data |= mask;
254 else
255 gc->bgpio_data &= ~mask;
256
257 gc->write_reg(gc->reg_set, gc->bgpio_data);
258
259 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
260}
261
262static void bgpio_multiple_get_masks(struct gpio_chip *gc,
263 unsigned long *mask, unsigned long *bits,
264 unsigned long *set_mask,
265 unsigned long *clear_mask)
266{
267 int i;
268
269 *set_mask = 0;
270 *clear_mask = 0;
271
272 for_each_set_bit(i, mask, gc->bgpio_bits) {
273 if (test_bit(i, bits))
274 *set_mask |= bgpio_line2mask(gc, i);
275 else
276 *clear_mask |= bgpio_line2mask(gc, i);
277 }
278}
279
280static void bgpio_set_multiple_single_reg(struct gpio_chip *gc,
281 unsigned long *mask,
282 unsigned long *bits,
283 void __iomem *reg)
284{
285 unsigned long flags;
286 unsigned long set_mask, clear_mask;
287
288 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
289
290 bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask);
291
292 gc->bgpio_data |= set_mask;
293 gc->bgpio_data &= ~clear_mask;
294
295 gc->write_reg(reg, gc->bgpio_data);
296
297 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
298}
299
300static void bgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
301 unsigned long *bits)
302{
303 bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_dat);
304}
305
306static void bgpio_set_multiple_set(struct gpio_chip *gc, unsigned long *mask,
307 unsigned long *bits)
308{
309 bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_set);
310}
311
312static void bgpio_set_multiple_with_clear(struct gpio_chip *gc,
313 unsigned long *mask,
314 unsigned long *bits)
315{
316 unsigned long set_mask, clear_mask;
317
318 bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask);
319
320 if (set_mask)
321 gc->write_reg(gc->reg_set, set_mask);
322 if (clear_mask)
323 gc->write_reg(gc->reg_clr, clear_mask);
324}
325
326static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio)
327{
328 return 0;
329}
330
331static int bgpio_dir_out_err(struct gpio_chip *gc, unsigned int gpio,
332 int val)
333{
334 return -EINVAL;
335}
336
337static int bgpio_simple_dir_out(struct gpio_chip *gc, unsigned int gpio,
338 int val)
339{
340 gc->set(gc, gpio, val);
341
342 return 0;
343}
344
345static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
346{
347 unsigned long flags;
348
349 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
350
351 gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
352
353 if (gc->reg_dir_in)
354 gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir);
355 if (gc->reg_dir_out)
356 gc->write_reg(gc->reg_dir_out, gc->bgpio_dir);
357
358 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
359
360 return 0;
361}
362
363static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)
364{
365 /* Return 0 if output, 1 if input */
366 if (gc->bgpio_dir_unreadable) {
367 if (gc->bgpio_dir & bgpio_line2mask(gc, gpio))
368 return GPIO_LINE_DIRECTION_OUT;
369 return GPIO_LINE_DIRECTION_IN;
370 }
371
372 if (gc->reg_dir_out) {
373 if (gc->read_reg(gc->reg_dir_out) & bgpio_line2mask(gc, gpio))
374 return GPIO_LINE_DIRECTION_OUT;
375 return GPIO_LINE_DIRECTION_IN;
376 }
377
378 if (gc->reg_dir_in)
379 if (!(gc->read_reg(gc->reg_dir_in) & bgpio_line2mask(gc, gpio)))
380 return GPIO_LINE_DIRECTION_OUT;
381
382 return GPIO_LINE_DIRECTION_IN;
383}
384
385static void bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
386{
387 unsigned long flags;
388
389 raw_spin_lock_irqsave(&gc->bgpio_lock, flags);
390
391 gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
392
393 if (gc->reg_dir_in)
394 gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir);
395 if (gc->reg_dir_out)
396 gc->write_reg(gc->reg_dir_out, gc->bgpio_dir);
397
398 raw_spin_unlock_irqrestore(&gc->bgpio_lock, flags);
399}
400
401static int bgpio_dir_out_dir_first(struct gpio_chip *gc, unsigned int gpio,
402 int val)
403{
404 bgpio_dir_out(gc, gpio, val);
405 gc->set(gc, gpio, val);
406 return 0;
407}
408
409static int bgpio_dir_out_val_first(struct gpio_chip *gc, unsigned int gpio,
410 int val)
411{
412 gc->set(gc, gpio, val);
413 bgpio_dir_out(gc, gpio, val);
414 return 0;
415}
416
417static int bgpio_setup_accessors(struct device *dev,
418 struct gpio_chip *gc,
419 bool byte_be)
420{
421
422 switch (gc->bgpio_bits) {
423 case 8:
424 gc->read_reg = bgpio_read8;
425 gc->write_reg = bgpio_write8;
426 break;
427 case 16:
428 if (byte_be) {
429 gc->read_reg = bgpio_read16be;
430 gc->write_reg = bgpio_write16be;
431 } else {
432 gc->read_reg = bgpio_read16;
433 gc->write_reg = bgpio_write16;
434 }
435 break;
436 case 32:
437 if (byte_be) {
438 gc->read_reg = bgpio_read32be;
439 gc->write_reg = bgpio_write32be;
440 } else {
441 gc->read_reg = bgpio_read32;
442 gc->write_reg = bgpio_write32;
443 }
444 break;
445#if BITS_PER_LONG >= 64
446 case 64:
447 if (byte_be) {
448 dev_err(dev,
449 "64 bit big endian byte order unsupported\n");
450 return -EINVAL;
451 } else {
452 gc->read_reg = bgpio_read64;
453 gc->write_reg = bgpio_write64;
454 }
455 break;
456#endif /* BITS_PER_LONG >= 64 */
457 default:
458 dev_err(dev, "unsupported data width %u bits\n", gc->bgpio_bits);
459 return -EINVAL;
460 }
461
462 return 0;
463}
464
465/*
466 * Create the device and allocate the resources. For setting GPIO's there are
467 * three supported configurations:
468 *
469 * - single input/output register resource (named "dat").
470 * - set/clear pair (named "set" and "clr").
471 * - single output register resource and single input resource ("set" and
472 * dat").
473 *
474 * For the single output register, this drives a 1 by setting a bit and a zero
475 * by clearing a bit. For the set clr pair, this drives a 1 by setting a bit
476 * in the set register and clears it by setting a bit in the clear register.
477 * The configuration is detected by which resources are present.
478 *
479 * For setting the GPIO direction, there are three supported configurations:
480 *
481 * - simple bidirection GPIO that requires no configuration.
482 * - an output direction register (named "dirout") where a 1 bit
483 * indicates the GPIO is an output.
484 * - an input direction register (named "dirin") where a 1 bit indicates
485 * the GPIO is an input.
486 */
487static int bgpio_setup_io(struct gpio_chip *gc,
488 void __iomem *dat,
489 void __iomem *set,
490 void __iomem *clr,
491 unsigned long flags)
492{
493
494 gc->reg_dat = dat;
495 if (!gc->reg_dat)
496 return -EINVAL;
497
498 if (set && clr) {
499 gc->reg_set = set;
500 gc->reg_clr = clr;
501 gc->set = bgpio_set_with_clear;
502 gc->set_multiple = bgpio_set_multiple_with_clear;
503 } else if (set && !clr) {
504 gc->reg_set = set;
505 gc->set = bgpio_set_set;
506 gc->set_multiple = bgpio_set_multiple_set;
507 } else if (flags & BGPIOF_NO_OUTPUT) {
508 gc->set = bgpio_set_none;
509 gc->set_multiple = NULL;
510 } else {
511 gc->set = bgpio_set;
512 gc->set_multiple = bgpio_set_multiple;
513 }
514
515 if (!(flags & BGPIOF_UNREADABLE_REG_SET) &&
516 (flags & BGPIOF_READ_OUTPUT_REG_SET)) {
517 gc->get = bgpio_get_set;
518 if (!gc->be_bits)
519 gc->get_multiple = bgpio_get_set_multiple;
520 /*
521 * We deliberately avoid assigning the ->get_multiple() call
522 * for big endian mirrored registers which are ALSO reflecting
523 * their value in the set register when used as output. It is
524 * simply too much complexity, let the GPIO core fall back to
525 * reading each line individually in that fringe case.
526 */
527 } else {
528 gc->get = bgpio_get;
529 if (gc->be_bits)
530 gc->get_multiple = bgpio_get_multiple_be;
531 else
532 gc->get_multiple = bgpio_get_multiple;
533 }
534
535 return 0;
536}
537
538static int bgpio_setup_direction(struct gpio_chip *gc,
539 void __iomem *dirout,
540 void __iomem *dirin,
541 unsigned long flags)
542{
543 if (dirout || dirin) {
544 gc->reg_dir_out = dirout;
545 gc->reg_dir_in = dirin;
546 if (flags & BGPIOF_NO_SET_ON_INPUT)
547 gc->direction_output = bgpio_dir_out_dir_first;
548 else
549 gc->direction_output = bgpio_dir_out_val_first;
550 gc->direction_input = bgpio_dir_in;
551 gc->get_direction = bgpio_get_dir;
552 } else {
553 if (flags & BGPIOF_NO_OUTPUT)
554 gc->direction_output = bgpio_dir_out_err;
555 else
556 gc->direction_output = bgpio_simple_dir_out;
557 gc->direction_input = bgpio_simple_dir_in;
558 }
559
560 return 0;
561}
562
563static int bgpio_request(struct gpio_chip *chip, unsigned gpio_pin)
564{
565 if (gpio_pin < chip->ngpio)
566 return 0;
567
568 return -EINVAL;
569}
570
571/**
572 * bgpio_init() - Initialize generic GPIO accessor functions
573 * @gc: the GPIO chip to set up
574 * @dev: the parent device of the new GPIO chip (compulsory)
575 * @sz: the size (width) of the MMIO registers in bytes, typically 1, 2 or 4
576 * @dat: MMIO address for the register to READ the value of the GPIO lines, it
577 * is expected that a 1 in the corresponding bit in this register means the
578 * line is asserted
579 * @set: MMIO address for the register to SET the value of the GPIO lines, it is
580 * expected that we write the line with 1 in this register to drive the GPIO line
581 * high.
582 * @clr: MMIO address for the register to CLEAR the value of the GPIO lines, it is
583 * expected that we write the line with 1 in this register to drive the GPIO line
584 * low. It is allowed to leave this address as NULL, in that case the SET register
585 * will be assumed to also clear the GPIO lines, by actively writing the line
586 * with 0.
587 * @dirout: MMIO address for the register to set the line as OUTPUT. It is assumed
588 * that setting a line to 1 in this register will turn that line into an
589 * output line. Conversely, setting the line to 0 will turn that line into
590 * an input.
591 * @dirin: MMIO address for the register to set this line as INPUT. It is assumed
592 * that setting a line to 1 in this register will turn that line into an
593 * input line. Conversely, setting the line to 0 will turn that line into
594 * an output.
595 * @flags: Different flags that will affect the behaviour of the device, such as
596 * endianness etc.
597 */
598int bgpio_init(struct gpio_chip *gc, struct device *dev,
599 unsigned long sz, void __iomem *dat, void __iomem *set,
600 void __iomem *clr, void __iomem *dirout, void __iomem *dirin,
601 unsigned long flags)
602{
603 int ret;
604
605 if (!is_power_of_2(sz))
606 return -EINVAL;
607
608 gc->bgpio_bits = sz * 8;
609 if (gc->bgpio_bits > BITS_PER_LONG)
610 return -EINVAL;
611
612 raw_spin_lock_init(&gc->bgpio_lock);
613 gc->parent = dev;
614 gc->label = dev_name(dev);
615 gc->base = -1;
616 gc->request = bgpio_request;
617 gc->be_bits = !!(flags & BGPIOF_BIG_ENDIAN);
618
619 ret = gpiochip_get_ngpios(gc, dev);
620 if (ret)
621 gc->ngpio = gc->bgpio_bits;
622 else
623 gc->bgpio_bits = roundup_pow_of_two(round_up(gc->ngpio, 8));
624
625 ret = bgpio_setup_io(gc, dat, set, clr, flags);
626 if (ret)
627 return ret;
628
629 ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER);
630 if (ret)
631 return ret;
632
633 ret = bgpio_setup_direction(gc, dirout, dirin, flags);
634 if (ret)
635 return ret;
636
637 gc->bgpio_data = gc->read_reg(gc->reg_dat);
638 if (gc->set == bgpio_set_set &&
639 !(flags & BGPIOF_UNREADABLE_REG_SET))
640 gc->bgpio_data = gc->read_reg(gc->reg_set);
641
642 if (flags & BGPIOF_UNREADABLE_REG_DIR)
643 gc->bgpio_dir_unreadable = true;
644
645 /*
646 * Inspect hardware to find initial direction setting.
647 */
648 if ((gc->reg_dir_out || gc->reg_dir_in) &&
649 !(flags & BGPIOF_UNREADABLE_REG_DIR)) {
650 if (gc->reg_dir_out)
651 gc->bgpio_dir = gc->read_reg(gc->reg_dir_out);
652 else if (gc->reg_dir_in)
653 gc->bgpio_dir = ~gc->read_reg(gc->reg_dir_in);
654 /*
655 * If we have two direction registers, synchronise
656 * input setting to output setting, the library
657 * can not handle a line being input and output at
658 * the same time.
659 */
660 if (gc->reg_dir_out && gc->reg_dir_in)
661 gc->write_reg(gc->reg_dir_in, ~gc->bgpio_dir);
662 }
663
664 return ret;
665}
666EXPORT_SYMBOL_GPL(bgpio_init);
667
668#if IS_ENABLED(CONFIG_GPIO_GENERIC_PLATFORM)
669
670static void __iomem *bgpio_map(struct platform_device *pdev,
671 const char *name,
672 resource_size_t sane_sz)
673{
674 struct resource *r;
675 resource_size_t sz;
676
677 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
678 if (!r)
679 return NULL;
680
681 sz = resource_size(r);
682 if (sz != sane_sz)
683 return IOMEM_ERR_PTR(-EINVAL);
684
685 return devm_ioremap_resource(&pdev->dev, r);
686}
687
688static const struct of_device_id bgpio_of_match[] = {
689 { .compatible = "brcm,bcm6345-gpio" },
690 { .compatible = "wd,mbl-gpio" },
691 { .compatible = "ni,169445-nand-gpio" },
692 { }
693};
694MODULE_DEVICE_TABLE(of, bgpio_of_match);
695
696static struct bgpio_pdata *bgpio_parse_fw(struct device *dev, unsigned long *flags)
697{
698 struct bgpio_pdata *pdata;
699
700 if (!dev_fwnode(dev))
701 return NULL;
702
703 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
704 if (!pdata)
705 return ERR_PTR(-ENOMEM);
706
707 pdata->base = -1;
708
709 if (device_is_big_endian(dev))
710 *flags |= BGPIOF_BIG_ENDIAN_BYTE_ORDER;
711
712 if (device_property_read_bool(dev, "no-output"))
713 *flags |= BGPIOF_NO_OUTPUT;
714
715 return pdata;
716}
717
718static int bgpio_pdev_probe(struct platform_device *pdev)
719{
720 struct device *dev = &pdev->dev;
721 struct resource *r;
722 void __iomem *dat;
723 void __iomem *set;
724 void __iomem *clr;
725 void __iomem *dirout;
726 void __iomem *dirin;
727 unsigned long sz;
728 unsigned long flags = 0;
729 int err;
730 struct gpio_chip *gc;
731 struct bgpio_pdata *pdata;
732
733 pdata = bgpio_parse_fw(dev, &flags);
734 if (IS_ERR(pdata))
735 return PTR_ERR(pdata);
736
737 if (!pdata) {
738 pdata = dev_get_platdata(dev);
739 flags = pdev->id_entry->driver_data;
740 }
741
742 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat");
743 if (!r)
744 return -EINVAL;
745
746 sz = resource_size(r);
747
748 dat = bgpio_map(pdev, "dat", sz);
749 if (IS_ERR(dat))
750 return PTR_ERR(dat);
751
752 set = bgpio_map(pdev, "set", sz);
753 if (IS_ERR(set))
754 return PTR_ERR(set);
755
756 clr = bgpio_map(pdev, "clr", sz);
757 if (IS_ERR(clr))
758 return PTR_ERR(clr);
759
760 dirout = bgpio_map(pdev, "dirout", sz);
761 if (IS_ERR(dirout))
762 return PTR_ERR(dirout);
763
764 dirin = bgpio_map(pdev, "dirin", sz);
765 if (IS_ERR(dirin))
766 return PTR_ERR(dirin);
767
768 gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);
769 if (!gc)
770 return -ENOMEM;
771
772 err = bgpio_init(gc, dev, sz, dat, set, clr, dirout, dirin, flags);
773 if (err)
774 return err;
775
776 if (pdata) {
777 if (pdata->label)
778 gc->label = pdata->label;
779 gc->base = pdata->base;
780 if (pdata->ngpio > 0)
781 gc->ngpio = pdata->ngpio;
782 }
783
784 platform_set_drvdata(pdev, gc);
785
786 return devm_gpiochip_add_data(&pdev->dev, gc, NULL);
787}
788
789static const struct platform_device_id bgpio_id_table[] = {
790 {
791 .name = "basic-mmio-gpio",
792 .driver_data = 0,
793 }, {
794 .name = "basic-mmio-gpio-be",
795 .driver_data = BGPIOF_BIG_ENDIAN,
796 },
797 { }
798};
799MODULE_DEVICE_TABLE(platform, bgpio_id_table);
800
801static struct platform_driver bgpio_driver = {
802 .driver = {
803 .name = "basic-mmio-gpio",
804 .of_match_table = bgpio_of_match,
805 },
806 .id_table = bgpio_id_table,
807 .probe = bgpio_pdev_probe,
808};
809
810module_platform_driver(bgpio_driver);
811
812#endif /* CONFIG_GPIO_GENERIC_PLATFORM */
813
814MODULE_DESCRIPTION("Driver for basic memory-mapped GPIO controllers");
815MODULE_AUTHOR("Anton Vorontsov <cbouatmailru@gmail.com>");
816MODULE_LICENSE("GPL");
1/*
2 * Generic driver for memory-mapped GPIO controllers.
3 *
4 * Copyright 2008 MontaVista Software, Inc.
5 * Copyright 2008,2010 Anton Vorontsov <cbouatmailru@gmail.com>
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
11 *
12 * ....``.```~~~~````.`.`.`.`.```````'',,,.........`````......`.......
13 * ...`` ```````..
14 * ..The simplest form of a GPIO controller that the driver supports is``
15 * `.just a single "data" register, where GPIO state can be read and/or `
16 * `,..written. ,,..``~~~~ .....``.`.`.~~.```.`.........``````.```````
17 * `````````
18 ___
19_/~~|___/~| . ```~~~~~~ ___/___\___ ,~.`.`.`.`````.~~...,,,,...
20__________|~$@~~~ %~ /o*o*o*o*o*o\ .. Implementing such a GPIO .
21o ` ~~~~\___/~~~~ ` controller in FPGA is ,.`
22 `....trivial..'~`.```.```
23 * ```````
24 * .```````~~~~`..`.``.``.
25 * . The driver supports `... ,..```.`~~~```````````````....````.``,,
26 * . big-endian notation, just`. .. A bit more sophisticated controllers ,
27 * . register the device with -be`. .with a pair of set/clear-bit registers ,
28 * `.. suffix. ```~~`````....`.` . affecting the data register and the .`
29 * ``.`.``...``` ```.. output pins are also supported.`
30 * ^^ `````.`````````.,``~``~``~~``````
31 * . ^^
32 * ,..`.`.`...````````````......`.`.`.`.`.`..`.`.`..
33 * .. The expectation is that in at least some cases . ,-~~~-,
34 * .this will be used with roll-your-own ASIC/FPGA .` \ /
35 * .logic in Verilog or VHDL. ~~~`````````..`````~~` \ /
36 * ..````````......``````````` \o_
37 * |
38 * ^^ / \
39 *
40 * ...`````~~`.....``.`..........``````.`.``.```........``.
41 * ` 8, 16, 32 and 64 bits registers are supported, and``.
42 * . the number of GPIOs is determined by the width of ~
43 * .. the registers. ,............```.`.`..`.`.~~~.`.`.`~
44 * `.......````.```
45 */
46
47#include <linux/init.h>
48#include <linux/err.h>
49#include <linux/bug.h>
50#include <linux/kernel.h>
51#include <linux/module.h>
52#include <linux/spinlock.h>
53#include <linux/compiler.h>
54#include <linux/types.h>
55#include <linux/errno.h>
56#include <linux/log2.h>
57#include <linux/ioport.h>
58#include <linux/io.h>
59#include <linux/gpio/driver.h>
60#include <linux/slab.h>
61#include <linux/bitops.h>
62#include <linux/platform_device.h>
63#include <linux/mod_devicetable.h>
64#include <linux/of.h>
65#include <linux/of_device.h>
66
67static void bgpio_write8(void __iomem *reg, unsigned long data)
68{
69 writeb(data, reg);
70}
71
72static unsigned long bgpio_read8(void __iomem *reg)
73{
74 return readb(reg);
75}
76
77static void bgpio_write16(void __iomem *reg, unsigned long data)
78{
79 writew(data, reg);
80}
81
82static unsigned long bgpio_read16(void __iomem *reg)
83{
84 return readw(reg);
85}
86
87static void bgpio_write32(void __iomem *reg, unsigned long data)
88{
89 writel(data, reg);
90}
91
92static unsigned long bgpio_read32(void __iomem *reg)
93{
94 return readl(reg);
95}
96
97#if BITS_PER_LONG >= 64
98static void bgpio_write64(void __iomem *reg, unsigned long data)
99{
100 writeq(data, reg);
101}
102
103static unsigned long bgpio_read64(void __iomem *reg)
104{
105 return readq(reg);
106}
107#endif /* BITS_PER_LONG >= 64 */
108
109static void bgpio_write16be(void __iomem *reg, unsigned long data)
110{
111 iowrite16be(data, reg);
112}
113
114static unsigned long bgpio_read16be(void __iomem *reg)
115{
116 return ioread16be(reg);
117}
118
119static void bgpio_write32be(void __iomem *reg, unsigned long data)
120{
121 iowrite32be(data, reg);
122}
123
124static unsigned long bgpio_read32be(void __iomem *reg)
125{
126 return ioread32be(reg);
127}
128
129static unsigned long bgpio_line2mask(struct gpio_chip *gc, unsigned int line)
130{
131 if (gc->be_bits)
132 return BIT(gc->bgpio_bits - 1 - line);
133 return BIT(line);
134}
135
136static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio)
137{
138 unsigned long pinmask = bgpio_line2mask(gc, gpio);
139
140 if (gc->bgpio_dir & pinmask)
141 return !!(gc->read_reg(gc->reg_set) & pinmask);
142 else
143 return !!(gc->read_reg(gc->reg_dat) & pinmask);
144}
145
146/*
147 * This assumes that the bits in the GPIO register are in native endianness.
148 * We only assign the function pointer if we have that.
149 */
150static int bgpio_get_set_multiple(struct gpio_chip *gc, unsigned long *mask,
151 unsigned long *bits)
152{
153 unsigned long get_mask = 0;
154 unsigned long set_mask = 0;
155
156 /* Make sure we first clear any bits that are zero when we read the register */
157 *bits &= ~*mask;
158
159 /* Exploit the fact that we know which directions are set */
160 set_mask = *mask & gc->bgpio_dir;
161 get_mask = *mask & ~gc->bgpio_dir;
162
163 if (set_mask)
164 *bits |= gc->read_reg(gc->reg_set) & set_mask;
165 if (get_mask)
166 *bits |= gc->read_reg(gc->reg_dat) & get_mask;
167
168 return 0;
169}
170
171static int bgpio_get(struct gpio_chip *gc, unsigned int gpio)
172{
173 return !!(gc->read_reg(gc->reg_dat) & bgpio_line2mask(gc, gpio));
174}
175
176/*
177 * This only works if the bits in the GPIO register are in native endianness.
178 */
179static int bgpio_get_multiple(struct gpio_chip *gc, unsigned long *mask,
180 unsigned long *bits)
181{
182 /* Make sure we first clear any bits that are zero when we read the register */
183 *bits &= ~*mask;
184 *bits |= gc->read_reg(gc->reg_dat) & *mask;
185 return 0;
186}
187
188/*
189 * With big endian mirrored bit order it becomes more tedious.
190 */
191static int bgpio_get_multiple_be(struct gpio_chip *gc, unsigned long *mask,
192 unsigned long *bits)
193{
194 unsigned long readmask = 0;
195 unsigned long val;
196 int bit;
197
198 /* Make sure we first clear any bits that are zero when we read the register */
199 *bits &= ~*mask;
200
201 /* Create a mirrored mask */
202 bit = -1;
203 while ((bit = find_next_bit(mask, gc->ngpio, bit + 1)) < gc->ngpio)
204 readmask |= bgpio_line2mask(gc, bit);
205
206 /* Read the register */
207 val = gc->read_reg(gc->reg_dat) & readmask;
208
209 /*
210 * Mirror the result into the "bits" result, this will give line 0
211 * in bit 0 ... line 31 in bit 31 for a 32bit register.
212 */
213 bit = -1;
214 while ((bit = find_next_bit(&val, gc->ngpio, bit + 1)) < gc->ngpio)
215 *bits |= bgpio_line2mask(gc, bit);
216
217 return 0;
218}
219
220static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val)
221{
222}
223
224static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
225{
226 unsigned long mask = bgpio_line2mask(gc, gpio);
227 unsigned long flags;
228
229 spin_lock_irqsave(&gc->bgpio_lock, flags);
230
231 if (val)
232 gc->bgpio_data |= mask;
233 else
234 gc->bgpio_data &= ~mask;
235
236 gc->write_reg(gc->reg_dat, gc->bgpio_data);
237
238 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
239}
240
241static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio,
242 int val)
243{
244 unsigned long mask = bgpio_line2mask(gc, gpio);
245
246 if (val)
247 gc->write_reg(gc->reg_set, mask);
248 else
249 gc->write_reg(gc->reg_clr, mask);
250}
251
252static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val)
253{
254 unsigned long mask = bgpio_line2mask(gc, gpio);
255 unsigned long flags;
256
257 spin_lock_irqsave(&gc->bgpio_lock, flags);
258
259 if (val)
260 gc->bgpio_data |= mask;
261 else
262 gc->bgpio_data &= ~mask;
263
264 gc->write_reg(gc->reg_set, gc->bgpio_data);
265
266 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
267}
268
269static void bgpio_multiple_get_masks(struct gpio_chip *gc,
270 unsigned long *mask, unsigned long *bits,
271 unsigned long *set_mask,
272 unsigned long *clear_mask)
273{
274 int i;
275
276 *set_mask = 0;
277 *clear_mask = 0;
278
279 for (i = 0; i < gc->bgpio_bits; i++) {
280 if (*mask == 0)
281 break;
282 if (__test_and_clear_bit(i, mask)) {
283 if (test_bit(i, bits))
284 *set_mask |= bgpio_line2mask(gc, i);
285 else
286 *clear_mask |= bgpio_line2mask(gc, i);
287 }
288 }
289}
290
291static void bgpio_set_multiple_single_reg(struct gpio_chip *gc,
292 unsigned long *mask,
293 unsigned long *bits,
294 void __iomem *reg)
295{
296 unsigned long flags;
297 unsigned long set_mask, clear_mask;
298
299 spin_lock_irqsave(&gc->bgpio_lock, flags);
300
301 bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask);
302
303 gc->bgpio_data |= set_mask;
304 gc->bgpio_data &= ~clear_mask;
305
306 gc->write_reg(reg, gc->bgpio_data);
307
308 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
309}
310
311static void bgpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
312 unsigned long *bits)
313{
314 bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_dat);
315}
316
317static void bgpio_set_multiple_set(struct gpio_chip *gc, unsigned long *mask,
318 unsigned long *bits)
319{
320 bgpio_set_multiple_single_reg(gc, mask, bits, gc->reg_set);
321}
322
323static void bgpio_set_multiple_with_clear(struct gpio_chip *gc,
324 unsigned long *mask,
325 unsigned long *bits)
326{
327 unsigned long set_mask, clear_mask;
328
329 bgpio_multiple_get_masks(gc, mask, bits, &set_mask, &clear_mask);
330
331 if (set_mask)
332 gc->write_reg(gc->reg_set, set_mask);
333 if (clear_mask)
334 gc->write_reg(gc->reg_clr, clear_mask);
335}
336
337static int bgpio_simple_dir_in(struct gpio_chip *gc, unsigned int gpio)
338{
339 return 0;
340}
341
342static int bgpio_dir_out_err(struct gpio_chip *gc, unsigned int gpio,
343 int val)
344{
345 return -EINVAL;
346}
347
348static int bgpio_simple_dir_out(struct gpio_chip *gc, unsigned int gpio,
349 int val)
350{
351 gc->set(gc, gpio, val);
352
353 return 0;
354}
355
356static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
357{
358 unsigned long flags;
359
360 spin_lock_irqsave(&gc->bgpio_lock, flags);
361
362 gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
363 gc->write_reg(gc->reg_dir, gc->bgpio_dir);
364
365 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
366
367 return 0;
368}
369
370static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)
371{
372 /* Return 0 if output, 1 of input */
373 return !(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));
374}
375
376static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
377{
378 unsigned long flags;
379
380 gc->set(gc, gpio, val);
381
382 spin_lock_irqsave(&gc->bgpio_lock, flags);
383
384 gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
385 gc->write_reg(gc->reg_dir, gc->bgpio_dir);
386
387 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
388
389 return 0;
390}
391
392static int bgpio_dir_in_inv(struct gpio_chip *gc, unsigned int gpio)
393{
394 unsigned long flags;
395
396 spin_lock_irqsave(&gc->bgpio_lock, flags);
397
398 gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
399 gc->write_reg(gc->reg_dir, gc->bgpio_dir);
400
401 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
402
403 return 0;
404}
405
406static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val)
407{
408 unsigned long flags;
409
410 gc->set(gc, gpio, val);
411
412 spin_lock_irqsave(&gc->bgpio_lock, flags);
413
414 gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
415 gc->write_reg(gc->reg_dir, gc->bgpio_dir);
416
417 spin_unlock_irqrestore(&gc->bgpio_lock, flags);
418
419 return 0;
420}
421
422static int bgpio_get_dir_inv(struct gpio_chip *gc, unsigned int gpio)
423{
424 /* Return 0 if output, 1 if input */
425 return !!(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));
426}
427
428static int bgpio_setup_accessors(struct device *dev,
429 struct gpio_chip *gc,
430 bool byte_be)
431{
432
433 switch (gc->bgpio_bits) {
434 case 8:
435 gc->read_reg = bgpio_read8;
436 gc->write_reg = bgpio_write8;
437 break;
438 case 16:
439 if (byte_be) {
440 gc->read_reg = bgpio_read16be;
441 gc->write_reg = bgpio_write16be;
442 } else {
443 gc->read_reg = bgpio_read16;
444 gc->write_reg = bgpio_write16;
445 }
446 break;
447 case 32:
448 if (byte_be) {
449 gc->read_reg = bgpio_read32be;
450 gc->write_reg = bgpio_write32be;
451 } else {
452 gc->read_reg = bgpio_read32;
453 gc->write_reg = bgpio_write32;
454 }
455 break;
456#if BITS_PER_LONG >= 64
457 case 64:
458 if (byte_be) {
459 dev_err(dev,
460 "64 bit big endian byte order unsupported\n");
461 return -EINVAL;
462 } else {
463 gc->read_reg = bgpio_read64;
464 gc->write_reg = bgpio_write64;
465 }
466 break;
467#endif /* BITS_PER_LONG >= 64 */
468 default:
469 dev_err(dev, "unsupported data width %u bits\n", gc->bgpio_bits);
470 return -EINVAL;
471 }
472
473 return 0;
474}
475
476/*
477 * Create the device and allocate the resources. For setting GPIO's there are
478 * three supported configurations:
479 *
480 * - single input/output register resource (named "dat").
481 * - set/clear pair (named "set" and "clr").
482 * - single output register resource and single input resource ("set" and
483 * dat").
484 *
485 * For the single output register, this drives a 1 by setting a bit and a zero
486 * by clearing a bit. For the set clr pair, this drives a 1 by setting a bit
487 * in the set register and clears it by setting a bit in the clear register.
488 * The configuration is detected by which resources are present.
489 *
490 * For setting the GPIO direction, there are three supported configurations:
491 *
492 * - simple bidirection GPIO that requires no configuration.
493 * - an output direction register (named "dirout") where a 1 bit
494 * indicates the GPIO is an output.
495 * - an input direction register (named "dirin") where a 1 bit indicates
496 * the GPIO is an input.
497 */
498static int bgpio_setup_io(struct gpio_chip *gc,
499 void __iomem *dat,
500 void __iomem *set,
501 void __iomem *clr,
502 unsigned long flags)
503{
504
505 gc->reg_dat = dat;
506 if (!gc->reg_dat)
507 return -EINVAL;
508
509 if (set && clr) {
510 gc->reg_set = set;
511 gc->reg_clr = clr;
512 gc->set = bgpio_set_with_clear;
513 gc->set_multiple = bgpio_set_multiple_with_clear;
514 } else if (set && !clr) {
515 gc->reg_set = set;
516 gc->set = bgpio_set_set;
517 gc->set_multiple = bgpio_set_multiple_set;
518 } else if (flags & BGPIOF_NO_OUTPUT) {
519 gc->set = bgpio_set_none;
520 gc->set_multiple = NULL;
521 } else {
522 gc->set = bgpio_set;
523 gc->set_multiple = bgpio_set_multiple;
524 }
525
526 if (!(flags & BGPIOF_UNREADABLE_REG_SET) &&
527 (flags & BGPIOF_READ_OUTPUT_REG_SET)) {
528 gc->get = bgpio_get_set;
529 if (!gc->be_bits)
530 gc->get_multiple = bgpio_get_set_multiple;
531 /*
532 * We deliberately avoid assigning the ->get_multiple() call
533 * for big endian mirrored registers which are ALSO reflecting
534 * their value in the set register when used as output. It is
535 * simply too much complexity, let the GPIO core fall back to
536 * reading each line individually in that fringe case.
537 */
538 } else {
539 gc->get = bgpio_get;
540 if (gc->be_bits)
541 gc->get_multiple = bgpio_get_multiple_be;
542 else
543 gc->get_multiple = bgpio_get_multiple;
544 }
545
546 return 0;
547}
548
549static int bgpio_setup_direction(struct gpio_chip *gc,
550 void __iomem *dirout,
551 void __iomem *dirin,
552 unsigned long flags)
553{
554 if (dirout && dirin) {
555 return -EINVAL;
556 } else if (dirout) {
557 gc->reg_dir = dirout;
558 gc->direction_output = bgpio_dir_out;
559 gc->direction_input = bgpio_dir_in;
560 gc->get_direction = bgpio_get_dir;
561 } else if (dirin) {
562 gc->reg_dir = dirin;
563 gc->direction_output = bgpio_dir_out_inv;
564 gc->direction_input = bgpio_dir_in_inv;
565 gc->get_direction = bgpio_get_dir_inv;
566 } else {
567 if (flags & BGPIOF_NO_OUTPUT)
568 gc->direction_output = bgpio_dir_out_err;
569 else
570 gc->direction_output = bgpio_simple_dir_out;
571 gc->direction_input = bgpio_simple_dir_in;
572 }
573
574 return 0;
575}
576
577static int bgpio_request(struct gpio_chip *chip, unsigned gpio_pin)
578{
579 if (gpio_pin < chip->ngpio)
580 return 0;
581
582 return -EINVAL;
583}
584
585int bgpio_init(struct gpio_chip *gc, struct device *dev,
586 unsigned long sz, void __iomem *dat, void __iomem *set,
587 void __iomem *clr, void __iomem *dirout, void __iomem *dirin,
588 unsigned long flags)
589{
590 int ret;
591
592 if (!is_power_of_2(sz))
593 return -EINVAL;
594
595 gc->bgpio_bits = sz * 8;
596 if (gc->bgpio_bits > BITS_PER_LONG)
597 return -EINVAL;
598
599 spin_lock_init(&gc->bgpio_lock);
600 gc->parent = dev;
601 gc->label = dev_name(dev);
602 gc->base = -1;
603 gc->ngpio = gc->bgpio_bits;
604 gc->request = bgpio_request;
605 gc->be_bits = !!(flags & BGPIOF_BIG_ENDIAN);
606
607 ret = bgpio_setup_io(gc, dat, set, clr, flags);
608 if (ret)
609 return ret;
610
611 ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER);
612 if (ret)
613 return ret;
614
615 ret = bgpio_setup_direction(gc, dirout, dirin, flags);
616 if (ret)
617 return ret;
618
619 gc->bgpio_data = gc->read_reg(gc->reg_dat);
620 if (gc->set == bgpio_set_set &&
621 !(flags & BGPIOF_UNREADABLE_REG_SET))
622 gc->bgpio_data = gc->read_reg(gc->reg_set);
623 if (gc->reg_dir && !(flags & BGPIOF_UNREADABLE_REG_DIR))
624 gc->bgpio_dir = gc->read_reg(gc->reg_dir);
625
626 return ret;
627}
628EXPORT_SYMBOL_GPL(bgpio_init);
629
630#if IS_ENABLED(CONFIG_GPIO_GENERIC_PLATFORM)
631
632static void __iomem *bgpio_map(struct platform_device *pdev,
633 const char *name,
634 resource_size_t sane_sz)
635{
636 struct resource *r;
637 resource_size_t sz;
638
639 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
640 if (!r)
641 return NULL;
642
643 sz = resource_size(r);
644 if (sz != sane_sz)
645 return IOMEM_ERR_PTR(-EINVAL);
646
647 return devm_ioremap_resource(&pdev->dev, r);
648}
649
650#ifdef CONFIG_OF
651static const struct of_device_id bgpio_of_match[] = {
652 { .compatible = "brcm,bcm6345-gpio" },
653 { .compatible = "wd,mbl-gpio" },
654 { .compatible = "ni,169445-nand-gpio" },
655 { }
656};
657MODULE_DEVICE_TABLE(of, bgpio_of_match);
658
659static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev,
660 unsigned long *flags)
661{
662 struct bgpio_pdata *pdata;
663
664 if (!of_match_device(bgpio_of_match, &pdev->dev))
665 return NULL;
666
667 pdata = devm_kzalloc(&pdev->dev, sizeof(struct bgpio_pdata),
668 GFP_KERNEL);
669 if (!pdata)
670 return ERR_PTR(-ENOMEM);
671
672 pdata->base = -1;
673
674 if (of_device_is_big_endian(pdev->dev.of_node))
675 *flags |= BGPIOF_BIG_ENDIAN_BYTE_ORDER;
676
677 if (of_property_read_bool(pdev->dev.of_node, "no-output"))
678 *flags |= BGPIOF_NO_OUTPUT;
679
680 return pdata;
681}
682#else
683static struct bgpio_pdata *bgpio_parse_dt(struct platform_device *pdev,
684 unsigned long *flags)
685{
686 return NULL;
687}
688#endif /* CONFIG_OF */
689
690static int bgpio_pdev_probe(struct platform_device *pdev)
691{
692 struct device *dev = &pdev->dev;
693 struct resource *r;
694 void __iomem *dat;
695 void __iomem *set;
696 void __iomem *clr;
697 void __iomem *dirout;
698 void __iomem *dirin;
699 unsigned long sz;
700 unsigned long flags = 0;
701 int err;
702 struct gpio_chip *gc;
703 struct bgpio_pdata *pdata;
704
705 pdata = bgpio_parse_dt(pdev, &flags);
706 if (IS_ERR(pdata))
707 return PTR_ERR(pdata);
708
709 if (!pdata) {
710 pdata = dev_get_platdata(dev);
711 flags = pdev->id_entry->driver_data;
712 }
713
714 r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat");
715 if (!r)
716 return -EINVAL;
717
718 sz = resource_size(r);
719
720 dat = bgpio_map(pdev, "dat", sz);
721 if (IS_ERR(dat))
722 return PTR_ERR(dat);
723
724 set = bgpio_map(pdev, "set", sz);
725 if (IS_ERR(set))
726 return PTR_ERR(set);
727
728 clr = bgpio_map(pdev, "clr", sz);
729 if (IS_ERR(clr))
730 return PTR_ERR(clr);
731
732 dirout = bgpio_map(pdev, "dirout", sz);
733 if (IS_ERR(dirout))
734 return PTR_ERR(dirout);
735
736 dirin = bgpio_map(pdev, "dirin", sz);
737 if (IS_ERR(dirin))
738 return PTR_ERR(dirin);
739
740 gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);
741 if (!gc)
742 return -ENOMEM;
743
744 err = bgpio_init(gc, dev, sz, dat, set, clr, dirout, dirin, flags);
745 if (err)
746 return err;
747
748 if (pdata) {
749 if (pdata->label)
750 gc->label = pdata->label;
751 gc->base = pdata->base;
752 if (pdata->ngpio > 0)
753 gc->ngpio = pdata->ngpio;
754 }
755
756 platform_set_drvdata(pdev, gc);
757
758 return devm_gpiochip_add_data(&pdev->dev, gc, NULL);
759}
760
761static const struct platform_device_id bgpio_id_table[] = {
762 {
763 .name = "basic-mmio-gpio",
764 .driver_data = 0,
765 }, {
766 .name = "basic-mmio-gpio-be",
767 .driver_data = BGPIOF_BIG_ENDIAN,
768 },
769 { }
770};
771MODULE_DEVICE_TABLE(platform, bgpio_id_table);
772
773static struct platform_driver bgpio_driver = {
774 .driver = {
775 .name = "basic-mmio-gpio",
776 .of_match_table = of_match_ptr(bgpio_of_match),
777 },
778 .id_table = bgpio_id_table,
779 .probe = bgpio_pdev_probe,
780};
781
782module_platform_driver(bgpio_driver);
783
784#endif /* CONFIG_GPIO_GENERIC_PLATFORM */
785
786MODULE_DESCRIPTION("Driver for basic memory-mapped GPIO controllers");
787MODULE_AUTHOR("Anton Vorontsov <cbouatmailru@gmail.com>");
788MODULE_LICENSE("GPL");